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Cluster models of condensed systems are often used to simulate the core-level spectra obtained with X-ray Photoelectron Spectroscopy, XPS, or with X-ray Absorption Spectroscopy, XAS, especially for near edge features.
Covalent functionalization of single-walled carbon nanotubes (SWCNTs) is a promising route to enhance the quantum yield of exciton emission and can lead to single-photon emission at room temperature.
In this work, we developed a general platform for the fabrication of transition metal oxide nanoparticles supported by a graphene foam (GF) by first coating it with a methacrylated gelatin (GelMA) hydrogel, which served as a 3D matrix for nanoparticle dispersion. The engineered GelMA/GF matrix was hydrophilic with good mechanical strength and high conductivity, therefore providing a good platform for the dispersion of a variety of metal/oxide precursors. Due to this platform, well-dispersed Co 3 O 4 nanoparticles with the smallest size of 3 nm assembled on the nitrogen-doped graphene foam (Co 3 O 4 /NGF). The crystalline transformation from a CoCl 2 [H 2 O] 2 precursor to Co 3 O 4 was revealed by in operando X-ray diffraction and absorption techniques. After applying Co 3 O 4 /NGF as a free-standing electrocatalyst for water splitting, the nanoparticles of size 3 nm exhibited optimal catalytic activity in alkaline media; the corresponding cell could promote water splitting at a current density of 10 mA cm -2 with only 1.63 V and exhibited excellent stability in a 25 h long-term operation. Our results demonstrate that the GelMA hydrogel-coated 3D graphene foam can be a promising platform for the design and fabrication of graphene-based multifunctional materials.
Continuum elasticity model reproduces the equilibrium shape of Cu nanocrystals squeezed between graphene layers and predicts universal shape.
ThO 2 and UO 2 nanoparticles synthesized using a COF-5 template exhibit unpassivated surfaces and provide insight into nanoscale properties of actinides.
The best catalyst for OER is Co@V B with η OER of 0.43 V followed by Ni@V C with η OER = 0.47 V. For the ORR process, the best catalyst is Rh@V B with η ORR of 0.40 V followed by Pd@V B and Pd@V C ( η ORR = 0.45 V).
We developed tgBoost a machine learning model to predict glass transition temperature ( T g) of organic species considering their molecular structure and functionality for better predictions of the phase state of secondary organic aerosols.
Process optimization in the latent space of functions via variational autoencoder (VAE) and Bayesian Optimization (BO). We demonstrate this to optimize the curl of a kinetic ferroelectric model.
We demonstrate how large language models (LLMs) can be adapted to domain-specific science topics by connecting them to a corpus of trusted documents.
Dry-gel synthesis of sheet-like Silicalite-1 single crystals featuring intracrystalline macropores and short b -axis dimension.
The NMC–RGO framework can reduce the contact area between solid electrolytes and carbon in the composite cathode while this unique structure can provide facile electron transport pathways to the NMC through the RGO framework.
N-doped carbon/FeCoCu catalysts exhibit excellent ORR performance, demonstrating outstanding rechargeability in Zn–air batteries. DFT calculations reveal enhanced conductivity and a favorable surface electronic structure for oxygen reactions.
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Results from the successful growth of high quality KH{sub 2}PO{sub 4} (KDP) crystals with incorporated TiO{sub 2} anatase nanoparticles and the characterization of these crystals using several complementary methods are presented. The study allowed the nature and distribution of macroscopic and microscopic defects in the KDP:TiO{sub 2} crystals to be clarified. The relationship between these defects and the distribution of TiO{sub 2} nanoparticles, and the influence of incorporated nanoparticles on the nonlinear optical properties of composite crystals in comparison with pure crystals were also elucidated. Visual observations, transmission and scanning electron microscopy have shown that the anatase nanoparticles were captured mainly by the pyramidal growth sector and, to a considerably lesser extent, by the prismatic growth sector. Energy dispersive x-ray analysis was able to confirm that the growth layer stacks contain the TiO{sub 2} particles. Fourier transformation infrared spectra have clearly shown the presence of an absorption band at about 800 cm{sup -1} in both KDP:TiO{sub 2} and TiO{sub 2}, and the disappearance of the band, associated with hydroxyl OH{sup -} groups on the TiO{sub 2} surface in KDP:TiO{sub 2}. Significant variation in the imaginary and real parts of the cubic nonlinear optical susceptibilities and refractive index changes at continuous wave excitation were found in prism and pyramid parts of pure KDP and KDP:TiO{sub 2} samples. Deciphering complicated electron paramagnetic resonance spectra in KDP:TiO{sub 2} and comparison with published data permitted the identification of paramagnetic defects along with their associated g-factors and zero-field splitting parameters (in some cases for the first time). It was found that the dominant lines belong to four different centers Fe{sub A}{sup 3+}, Fe{sub B}{sup 3+}, Cr{sub R}{sup 3+}, and Cr{sub GB}{sup 3+}. From analysis of line intensities it was concluded that the concentration of intrinsic defects like potassium and hydrogen vacancies in KDP:TiO{sub 2} is comparatively small, that the concentration of non-controlled impurities in nominally pure KDP samples is several times larger than in KDP:TiO{sub 2}, and that the concentration of non-controlled impurities in the prismatic part of the KDP:TiO{sub 2} boule is approximately twice as large as in the pyramid part.